Electric motors include a type in which motor coils are connected via an insulating terminal block to an external circuit. In this type of motor, a rotational position detecting circuit is provided integrally in the terminal block so that efficiency in assembly of the terminal block to the motor is improved. In this case, Hall elements serving as a rotation sensor and a heat sensitive element serving as a temperature sensor are fitted into element mounting portions after an electrically conductive plate has been formed by insert molding in the forming of the terminal block. A secondary formation is then carried out so that the rotational position detecting circuit is formed integrally. Japanese Patent No. 3497684 discloses an electric motor constructed as described above, for example.